如何在Objective-C中构建类方法的NSArray(或NSMutableArray)？

#import<Foundation/Foundation.h>

@interface MyClass : NSObject

+ (NSArray *)myArray;
+ (NSMutableArray *)myMutableArray;

@end

@implementation MyClass

+ (NSArray *)myArray {
    return @[@1, @2, @3];
}

+ (NSMutableArray *)myMutableArray {
    return [NSMutableArray arrayWithObjects:@1, @2, @3, nil];
}

@end

#import "MyClass.h"

@implementation AppDelegate

- (void)applicationDidFinishLaunching:(UIApplication *)application {
    NSArray *array = [MyClass myArray];
    NSMutableArray *mutableArray = [MyClass myMutableArray];
}

@end